How can I use TV15 Host on Windows 2019 Core Server?

According to the information on the TeamViewer website, this has never worked before. But I only stumbled across it now, because I never had to worry about it. I had unknowingly always installed the TV15 Host on Windows 2019 Core systems and it worked. But strangely, on new systems since the end of 2020, the host can be installed, it is also shown in the dashboard as accessible/available, but I can't connect to it, it just remains a black screen. But since I already have some systems with Windows Server Core 2019 and it works there, it must have something to do either with MS and newer versions or the newer TV15 host versions. Either way, it would be very helpful if someone knew what to do to get it running again and could post it here. Thanks to all!